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arXiv · 1704.05609

Coexistences of lamellar phases in ternary surfactant solutions

Isamu Sou·Ryuichi Okamoto·Shigeyuki Komura·Jean Wolff
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Abstract

We theoretically investigate the coexistences of lamellar phases both in binary and ternary surfactant solutions. The previous free energy of a lamellar stack is extended to take into account the translational entropy of membrane segments. The obtained phase diagram for binary surfactant solutions (surfactant/water mixtures) shows a phase separation between two lamellar phases and also exhibits a critical point. For lamellar phases in ternary surfactant solutions (surfactant/surfactant/water mixtures), we explore possible phase behaviors and show that the phase diagrams exhibit various three-phase regions as well as two-phase regions in which different lamellar phases coexist. We also find that finite surface tension suppresses undulation fluctuations of membranes and leads to a wider three-phase and two-phase coexistence regions.

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Isamu Sou, Ryuichi Okamoto, Shigeyuki Komura, Jean Wolff. 2017-04-19. Coexistences of lamellar phases in ternary surfactant solutions. https://arxiv.org/abs/1704.05609

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